Make scrubbing a MediaControls-internal concept

Source/core/html/shadow/MediaControls.h

Index: Source/core/html/shadow/MediaControls.h
diff --git a/Source/core/html/shadow/MediaControls.h b/Source/core/html/shadow/MediaControls.h
index 669b295eb0d9a6c48c33c60505e8082ad1feeee5..0706645afb8f77ac925e566bc41f51fb7f143fea 100644
--- a/Source/core/html/shadow/MediaControls.h
+++ b/Source/core/html/shadow/MediaControls.h
@@ -51,6 +51,9 @@ public:
     void playbackProgressed();
     void playbackStopped();
 
+    void beginScrubbing();
+    void endScrubbing();
+
     void updateCurrentTimeDisplay();
 
     void changedMute();
@@ -73,6 +76,8 @@ private:
     void makeOpaque();
     void makeTransparent();
 
+    void updatePlayState();
+
     bool shouldHideFullscreenControls();
     void hideFullscreenControlsTimerFired(Timer<MediaControls>*);
     void startHideFullscreenControlsTimer();
@@ -113,8 +118,9 @@ private:
     MediaControlPanelEnclosureElement* m_enclosure;
 
     Timer<MediaControls> m_hideFullscreenControlsTimer;
-    bool m_isFullscreen;
-    bool m_isMouseOverControls;
+    bool m_isFullscreen : 1;
+    bool m_isMouseOverControls : 1;
+    bool m_isPausedForScrubbing : 1;
 };
 
 DEFINE_ELEMENT_TYPE_CASTS(MediaControls, isMediaControls());